NFSD: Skip close replay processing if XDR encoding fails

The replay logic added by commit 9411b1d4c7df ("nfsd4: cleanup
handling of nfsv4.0 closed stateid's") cannot be done if encoding
failed due to a short send buffer; there's no guarantee that the
operation encoder has actually encoded the data that is being copied
to the replay cache.

Reported-by: rtm@csail.mit.edu
Closes: https://lore.kernel.org/linux-nfs/c3628d57-94ae-48cf-8c9e-49087a28cec9@oracle.com/T/#t
Fixes: 9411b1d4c7df ("nfsd4: cleanup handling of nfsv4.0 closed stateid's")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 6040a6145dad8556fa5e5b47be44828b860a1b9a..cf5df0f502089a8bced51dff40d7b9fff9aa39ab 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -5925,8 +5925,7 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
                 */
                warn_on_nonidempotent_op(op);
                xdr_truncate_encode(xdr, op_status_offset + XDR_UNIT);
-       }
-       if (so) {
+       } else if (so) {
                int len = xdr->buf->len - (op_status_offset + XDR_UNIT);
 
                so->so_replay.rp_status = op->status;